Engine-fuel-supply system



A. BUCH].

ENGINE FUEL SUPP'LY SYSTEM.

APPLICATION FILED AUG, 17, 1916.

Patented July 12, 1921.

R6 EIL- 33 affozuci '7? UNITED STATES PATENT OFFICE.

ALFRED IBU'CHI, or wm'rna'rnua, SWITZERLAND, assronoa 'ro nnscms iz BBOS.-DIESEL ENGINE comrnmr, on ST. LOUIS, nrssoum, a coaronarron or MISSOURI.

Specification of Letters Patent.

Patented July 12, 1921.

application filed August 17, 1916. Serial No. 115,396.

To all whomitmag concern:

Be it known that I, ALFRED BiioHI, a citizen of the Republic of Switzerland, residing in Winterthur, in the. Canton of Zurich, Switzerland, have invented certain new and useful Improvements in Engine-Fuel- Supply Systems, of which the following is a full, true, and complete specification.

This invention relates to heavy oil internal combustion engines operating on fuel of viscous character which is rendered sufficiently fluid to move freely through the fuel supply system by the application of heat, the partlcular'object of the invention being to maintain a proper temperature and degree of fluidity for all conditions of engine operation, that is to say when the fuel demand is heavy as well as when it is light, and thereby to provide for accurate and satisfactory engine regulation and operation. The oil is conducted from the reservoir or supply source to a heater by means of parts or piping wherein a relatively large body of oil is kept in agitation or circulation, the amount being sufficiently large with relation to the requirements of the engine to permit the entrance of fresh oil thereto, from the reservoir corresponding to the withdrawal for the engine, without appreciabl altering its temperature, and the heat supp ied is sufiicient to maintain a substantially constant supernormal temperature therein suited to preserve a requisite degree of fluidity.

The accompanying drawing illustrates schematically an embodiment of the invention.

An engine of the character stated is represented at a, with an exhaust pipe I) and fuel valve 0, whereby the liquid fuel is admitted to the cylinder in well-known manner. The fuel njection pump (Z which delivers the fuel in proper quantity through pipe 8 to the fuel valve is operated from the upright, engine-driven shaft k, and may be subject to the customary, hand or governor, regulation to vary the fuel feed in accordance with the load. The said pump draws its supply from a circulatory loop f, the

' piping of which is shown as of somewhat rger diameter than the injection line 8. Included in this loop is a coil 73 encircling the exhaust pipe, and representing in the quate natural circulation by the thermal f t e variation of the density 0 liquid in the loop. In the arrangement shown the said pump g is supplemental to and assists the natural thermal circulation, drawing the warmed fuel from the upper end of the heater coil 11 and delivering it part throughexternal branch pipe m to the inlet of injection pump (1, and the remainder throu h the internal branch f forming part of the loop and containing a valve n.

he fuel reservoir e is preferably external to the loop, being connected therewith at a point in the descending or cooler side of the system by a valved connection 1' of minimum length. The oil passes through this connection at a rate equivalent to the discharge through the injection valve, enters immediately into a heated circulating stream with which it mingles andby which it is warmed. Thecoil 4, shown inside the reservoir 6 is for preheating the fuel therein when necessary, by means of steam or hot gases. The circulatory system is so proportioned and adjusted in its various parts as to allow the oil to flow or circulate between the entrance from the reservoir and the exit to the injection pump (1, in volume considerably in excess of the immediate needs of the engine, so that a suflicient amount of heated oil will always be returned through the section. f to keep ,the piping warm and oil in pump d and the injection line 8 in a desired fluid state. When the exhaust pipe serves as the source of heat, as in the present case, the temperature of the injection line is kept practically constant and the accuracy of is opened and the valve 7" is closed just be-' fore the engine is to be shut down so as to fill the circulating system with the,lighter fuel in readiness for use whenever the enine is to be started. When the exhaust pipe has become hot the setting of the valves is reversed and the combustion thereafter proceeds on the heavy oil as above described. I

The means for circulating the liquid in the loop need not necessarily be dependent upon the engine, as is suggested by a pump represented diagrammatically-at 9 which pump may be driven by any available source of power other than the engine Such independent circulating means may be operated when the preheater p, also not dependent upon the operation of the engine, is in use, thus enabling the engine to be quickly started upon the regular or viscous fuel.

1. The combination with an internal combustion engine using normally viscous fuel and a supply source of such fuel, of means for heating and circulating a mass of said fuel in liquid form between the source and the engine, whereby the engine is served with liquid fuel drawn from a circulation of heated oil in excess of its immediate re-' quirements. t

2. The combination with an internal'combustion engine using normally viscous fuel, of a supply source of such fuel, a 100 circulating system v therefor, external 0 and connected to said source; and means wherebythe heat of the engines combustion is transmitted to the fuel in saidloop system. 3.The combination with a heavy oil internal combustion en 'ne, of aheater for the oil, means whereb ti circulated through from and heater at a rate in excess of the. rate of fuel consumption of the engine, a fuel valve sup plied by saidcircuit and a fuel. source also connected thereto and serving to replenish said circuit. V 4. The combination with a heavy oil internal combustion engine havin a fuel valve and means for feeding liquid o1l thereto, of

. a heater connected with the fuel feeding means, a source of supply also' connecte thereto, and means compmsmg 1 a loop circulating system for conducting quid oil from e oil in li uid form is ackto the the source through the heater to said feeding means, said loop system embodying means other than said'fuel feeding means for circulating the liquid oil at a rate exceeding the requirements of the engine.

5. The combination with a heavy oilinternal combustion engine having-fuel injecting means and an injection pump and oil line connected therewith, of a heater for the oil, a sourceof oil supply, and a loop external of and connected with the source of supply and including the heater, whereby a circulation-of heated. oil in excess of the requirements of the engine is maintained, said pump having its suction connected to the loop.

, 6. Thecombination with a heavy oil internal combustion engine having a liquid fuel intake, a reservoir, means between said fuel intake and-reservoir containin a body of liquid fuel, heating means for t e liquid fuel in said. means, a' ump for agitating the oil being heated, and means rece1ving heated liquid fuel from the first mentioned means and delivering the same to which liquid fuel circulates at a rate exceeding the requirements of the engine, and

means for heating the oil in-circuit by the waste heat of the engine.

8. The combination in an internal con1bus tion engine using normally viscous liquid fuel, of a fuel supply system, therefor including an injection pump, means supplying liquid fuel to said pump, and automatic means for imparting a substantially constant supernormal temperature to the liquid fuel movin to said pump.

9. e combination in an internal combustion engine using heavyv liquid fuel, of a reservoir an injection pump, a fuel supply system deliveringli 'uid fuel to said pump and' containing a re atively large body of [fuel between said pump and the reservoir,

and means for malntaining a substantially constant supernormalf temperature in saidbody of fuel. 10. The combination in an internal combustion engine using normally viscous liquid fuel, of a fuel injection valve, fuel supply means comprisin a loop circulating system for the fuel oil a apted to pass oil at a rate exceeding the re ulrements of the engine, a source of supp yconnected with and ex-- terior to the loop, means forwithdrawing oil from the loo to serve the injection valve, and-means for eating the oi l.in circuit in the 100%). 11; he combination inan. internal combustion engine, of a fuel reservoir, a circu- Ia-ting system receiving fuel therefrom and duce a thermal circulation in said system, and means for withdrawing heated fuel from said system for the'use of the engine.

12. The combination in an internal combustion engine using heavy liquid fuel, of a circulating fuel system embodying heating means arranged to induce a thermal circulation of liquid fuel therein, a fuel reservoir connected to supply fuel to said system on the cooler side thereof, and means for with- 10 drawing heated liquid fuel from said system for the use of the en ine.

In testimony whereoffI have signed this specification in the presence of two witnesses. ALFRED BUCHI. Witnesses:

CARL GuBLUoK, 0143A Ame. 

